Cannot pulse

Hello out there.

i currently have almost 500k keys and would like to pulse this, but cant. Whenever i try to pulse, theres either no reaction at all, or it shows the grey up arrow for a moment and thats it. Nothing else happens, no message, and i still got my keys and everything.

Im running the latest version on Win 7 64bit with admin privileges.

Minimize all windows make sure ‘No automated popups’ is not turned on in your settings and pulse again. It will give a messagebox with an error if there is one.